Abstract
1. Simple methods are described by which wireworms could be offered the choice of two alternative moistures. 2 . An account is given of the construction of a burrow. The extension of the burrow system by a single larva falls off with time; it is probable that under natural conditions such a system is semipermanent. 3. Wireworms migrate rapidly out of dry sand and aggregate in wet sand. This is due solely to the differential effect of moisture on the burrowing activity (ortho-kinesis). 4. Burrowing wireworms do not respond to gravity. 5. The feeding activity of a small population of larvae was found to be much greater at low than at high moistures. This is partly the result of the inactivity of the larvae when exposed to high moistures, and their consequent failure to reach the food. The presence of excess moisture, however, also has the effect of inhibiting all muscular activity, and this influences the manipulation of the mouth parts during feeding and locomotion alike. 6. These results are in good agreement with a number of purely ecological observations on wireworm behaviour.